“I did not quote improperly. Only the KJV uses the word doctrine rather than teaching. It is also one of the only ones to use the word perfect rather than equipped, prepared, furnished, competent etc.....”
The Vulgate and Webster translate it the same way (well, though the vulgate says “perfectus” lol), which I immediately have on my computer. I’m pretty sure others have it that way too.
As for the difference between teaching and doctrine... ummm. I can’t think of any.
Teaching is different than doctrine in numerous ways. In Timothy, teaching is used as a verb, as in what one does with Scripture.
There are many teachings that are not doctrine. For example, Jesus teaches us that the Sabbath is made for man, not man for the Sabbath. A conflict with the way the Jews understood the commandment. But, the command to keep the day holy is not changed.
Doctrine is a defined believe that is binding on the believers.